function [ sum ] = hl_feat_func( x, y, seg, tags )

    sum = 0;
    n = size(x,2);
    for i = 1:n-1
%         i
%         [y(i-1), y(i)]
        sum = sum + ll_feat_func(y(i), y(i+1), x, i, seg, tags);
    end
end

